The Zohar appeared in Castile c. 1280, circulated by Moses de Leon, written in an artificial Aramaic flavored with medieval Spanish traces. It presents itself as the teachings of Shimon bar Yochai (2nd century) and became Kabbalah's core commentary on the Torah. Gershom Scholem's philology established the medieval authorship.
The traditional counter: Shimon wrote it in the cave where he hid from Rome for thirteen years, and de Leon merely recovered the manuscript. Devout scholarship still argues early strata; the cave remains the community's anchor story.
The Zohar's actual innovation: Scripture read as the body's surface of an infinite God, every verse a window into the sefirot. Whether or not the attribution was honest, the reading technology it installed, symbol over literalism at industrial scale, changed Judaism permanently.
If a pious forgery becomes scripture, what does that make scripture?